Hours before a televised leaders' debate in Dublin, Kenny met Merkel in Berlinand said changing the 12.5% tax rate was not acceptable to any Irish government led by him.

The bookies' and pollsters' favourite to become taoiseach on 25 February relayed his belief that the interest Ireland is paying on loans related to the IMF/European Central Bank bailout is too high.

"I made it perfectly clear to the chancellor that, from our point of view, the corporation tax and the consolidated tax base are of absolute fundamental importance to Ireland and that we could not concede any movement on those," Kenny said after the meeting.

Kenny said Merkel was "very much aware of how important the issue is in Ireland". Fine Gael and Merkel's Christian Democratic Union are both members of the centre-right European People's party, the largest grouping in the European parliament.

One of Kenny's first setpiece events if he becomes prime minister will be to attend a European financial summit in March to rescue the eurozone and in particular those countries such as Ireland, Greece and Portugal mired in financial crises.

The Fianna Fáil leader, Micheál Martin, dismissed Kenny's trip to Berlin as a "photo-opportunity to make himself look prime ministerial".

Divisions between Fine Gael and its traditional coalition partner, the Irish Labour party, are widening.

Labour's Roisin Shortall claimed there was a "€5bn black hole" in Fine Gael's economic programme while party leader Eamon Gilmore accused Kenny and his colleagues of "siding with bankers".

Fianna Fail election candidate Pat Carey said a growing divide between Labour and Fine Gael showed they would make an unstable government unable to cope with the fiscal and banking crisis.

Carey said: "Most significant is the gulf that now exists between the so-called alternative government partners on banking and economic policy.

"As Labour and Fine Gael continue to fundamentally disagree over the serious issues in this campaign, voters are engaged more than ever. We are offering a real, credible plan to create an environment in which jobs can be created, the economy can grow and the way politics works in Ireland can be reformed."

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